Try to upgrade your desktop GUI to 7.5.0.3. I also had all sorts of 'weird' issues on Java GUI until I upgraded my desktop GUI.
If this does solve the issue, we need to start looking at catalog search/browse process on master.
Check that bpdbm and bprd log folders exist on the master. NBU needs to be restarted to enable these logs.

Supporting Storage Foundation and VCS on Unix and Windows as well as NetBackup on Unix and WindowsHandy NBU Links